Apparatus for heat treating and quenching



J y 19 1. J. M. NAI RN mm 2,2

APPARATUS FOR HEAT TREATING AND QUENCHING Filed Sept. 23, 1939 3 Sheets-sheaf l IN VENTO RS: JOHN IV. NAIR/V, WILLIAM 6. 'JA CKS 0A; BY

THE/R A170 RNE K July 15,1941.

J. M. NAIRN ETAL APPARATUS FOR HEAT TREATING AND QUENCHING Filed Sept. 25, 1959 3 sheets sheet 2 INVENTORS JOHN M. NA/RN, WILLIAM G. JACKSON, av

THE/R ATTO RNF)? Fig 9 July 15,1941. J. M. NAIRN ErAL APPARATUS FOR HEAT TREATING AND QUENCHING N am RRK M m m NAA E v a w M fl w M I OL .l w M W Y /a m m THEIR ATTORNEY Patented July 15, 1941 APPARATUS FOR HEAT TREATIN AND QUENCH'ING" John M. Nairn, East Orange, and William.G. t Jackson, Jersey City, N. J.-, assignors to Gen?- eral Motors Corporation, Detroit, Mich., a corporation of Delaware Application September 23, 1939, Serial No. 296,274

is Claims.

This invention relates to apparatus for heat treating and quenching articles and comprises all of the features of novelty herein disclosed. An object of the invention is to provide improved apparatus for handling articles and their'containers in connection with a c'arburizing and quenching operation or the like. Another object is to provide improved apparatus to handle large quantities of small parts as they come from a furnace with no risk to the operator and with minimum exertion. Another object is to provide simple, safe and easily controlled means for handling hot miscellaneous loose articles through a quenching cycle.

To these ends and also to improve generally upon apparatus of this character, the invention consists in the various matters hereinafter described and claimed. In its broader aspects, the invention is not necessarily limited to the specific construction selected for illustrative purposes in the accompanying drawings in which Fig. 1 is a plan view of the apparatus indicating three positions of the jib crane.

Fig. 2 is an end view of Fig.1 with the quench tanks omitted.

table with the standards attached.

Fig. 9 is an end view of Fig. 8.

Fig. 10 is a side view of Fig. 8, with parts in section.

Fig. 11 is a side view of an alternative construction of the quenching container.

Fig. 12 is a perspective View of the skeleton container or perforated basket.

Fig. 13 is an enlarged sectional view of a detail of Fig. 11.

Outlining first the preferred general operation, articles to be carburized are placed in skeleton metal containers or perforated baskets and pushed through a continuous tray-type of gas carburizing furnace. The baskets are successively moved out of the furnace onto a table which is tiltably mounted on a jib crane which can swing through successive arcs of 90. The crane first moves the table and the article-carrying basket-into proximity to -a quenching tank Where the table is tiltedto control discharge of the articles'from the basket into a second perforated container in the tank. fhe table and.

the empty basket are then righted and the jib crane-swingsanother 90* into proximity to a return conveyoronto which the empty basket is pushed for return to the front of the furnace for further use. When the quenched articles in the second perforated container are cool, the

container is'raised from the tank by elevating mechanism andslid out onto agravity conveyor or ontotracks extending lengthwise over the tank. Asthe perforated container moves over the tank, the residual quenching liquid drains out and the articles are removed from the container or dumped out at the'endof the conveyor. The crane swings back 180 to return the table to receiving-relation to the furnace.

The numeral l0 indicates the rear end of a gas carburizingfurnace from which the articles are transferred by the basket of Fig. 12 to a quenching tank l'2 whereupon the basket which has dumped the articles'into the tank goes'on. to a return conveyor [4 which is preferably a drag type chain conveyor.- The basket is carried by a tiltable-table l6 which occupies the three 1 positions indicated in Fig." 1 as such table is swung around by ajib crane; As shown in Fig. 2. a base plate It having a thrust bearing is bolted to a floor or foundation 22. A swivel pin 24 projects downwardly into the thrust hearing from a plate 26 securedto the bottoin'of a mast 28 of I-beam construction the pin'being welded in the cut-away web of the mast; A similar swivel pin 30 projects upwardly-from the top of the mast-"and is journalled in a bearing 32 on a bent bracket 34 which is secured at one end to a channeliron 36 on the side ofthe furnace and at the other end to a channel'iron'38 at the rear end of thefurnace; Secured by angle pieces flnear the top of the mast is a-horizontal crane or arm 42 braced from the mast by the angle iron 44'.

Boxes #6 containing roller bearings are welded 'to' plates 48 inturn welded to plates 50 which are welded tothe flanges of the crane 42. For a, purpose that will later appear, lugs 52 having guide of the motor to control the rate of spill but normally occupies a horizontal position resting on channel iron 'supports 66 which are welded on the crane.

The table I6 has a series of tracks or rails 68 which are rounded off at the ends and on a level with the usual rails in the furnace. At each side of the table are bolted a pair of standards I connected by a shouldered spacing bolt 12 threaded to receive nuts. The standards have projecting retaining lugs I4 adapted vto overlie a skeleton container or perforated basket I6 which contains the heat treated articles. The basket is conveniently made of U-shaped ribs I8 and bars 80 welded to surrounding straps. Each basket with its supporting tray is slid from the furnace rails through an exit opening 8| in the furnace onto the rails 68 and the lugs I4 hold the basket and tray on the table when the latter is tilted as indicated in Fig. 3. A-movable stop 82 on a rock shaft 84 projects through a slot in the table to limit endwise movement of the tray and the basket on the rails, thus helping the lugs I4 to hold the basket in dumping position. The rock shaft 84 is journalled in bearings 86 welded on the bottom of the table and eachend has an operating handle 88.

To lock the jib crane in its three positions, the base plate plate I8 has three holes for a vertical locking plunger 92 guided in the plate 26 and urged downwardly by a tension spring 94. The plunger is connected to a rod 96 guided in an angle bracket 98 and connected to a pivoted bell crank lever I00 having an operating rod I02 guided in the above mentioned apertured lugs 52. The rod I02 extends to the end of th crane arm 42 where it has an eye for convenient actuation.

The quenching tank I2 extends into a recess in the floor and contains a second perforated container I04 which rests on a grating I06 supported by horizontal angle irons I08 braced by gusset plates IIO from a pair of vertical angle irons H2. The angle irons II2 are connected by plates H4 and by U-shaped straps II6 carrying rollers II8 running vertically between flanges of vertical channel iron guides I20 which are fastened to the floor and to the tank. A piston rod I22 from a suitable air operated cylinder is connected to the upper strap II6 and-serves to raise and lower the container and its supporting elevator. The container can be elevated onto a level with a gravity conveyor I24 which extends lengthwise over the top of the quenching tank to a discharge station I26.

As an alternative to the container I 04, this second container may be in the form of a dumping car as indicated in Figs. 11 and 13. The car frame comprises channel iron sides I30, an end channel I32 and an angle iron cross bar I34 all welded together. Flanged wheels I36 rotatatbly mounted on the car frame run on tracks I40 secured to the grating I06, the tracks being curled up at one end as indicated at I42 to serve as a stop in one direction. The frame rockably supports a perforated dumping hopper I44 having rocker segments I46 secured to each side. Each segment has a series of retaining pins I48 adapted to enter holes I50 in the upper surface of the side frames on which the segments roll. A stop plate I52 is bolted to each side frame and the hopper is held from rolling by a pivoted latch I54 having a hook I56 to catch the end of the segment I46. Tracks I58 are fixed in position along the gravity conveyor I24 andover the tank in line with the tracks I40 so that the car can travel over the tank to a dumping position and back to the elevating mechanism. The lower part of the tank contains the usual oil distributing box I60 and oil pressure line I62.

In operation, the batches of articles go through the furnace I0 in the perforated baskets I6 supported by or integral with the usual sliding trays and are pulled out manually onto the table I6 against the stop- 62. The crane 42 is swung 90 and the motor 58 is started to control tilting of the table thereby discharging the hot articles at a controlled rate from the basket into the quenching liquid in the perforated container I04 (or the hopper I44). The table is then righted and the crane swung another 90 to carry the empty basket and tray to the return conveyor I4 I by which the basket and tray are carried back to the front end of the furnace for fruther use. The container I04 is then lifted by the elevating mechanism up to a level with the gravity conveyor I24 on which it is pushed for travel over the tank to the discharging station, the quenching liquid draining into the tank. If the dumping hopper I44 is used, its wheeled support runs on the tracks I58. Thus large quantities of small parts can be efficiently handled for carburizing and quenching without manual lifting and Without risk to the operator.

We claim:

1. In apparatus of the character indicated, a furnace, an article-containing basket adapted to travel through the furnace, a quenching tank, a crane to carry the basket from the furnace into proximity to the tank, a pivoted member on the crane, means to secure the basket to the pivoted member, and means on the crane for tilting the member and basket around the pivot to dump the articles into the tank; substantially as described.

2. In apparatus of the character indicated, a furnace, an article-containing basket adapted to travel through the furnace, a quenching tank, a return conveyor, a crane to carry the basket successively from the furnace to the tank and from the tank to the conveyor, and means on the crane for tipping the basket to dump the articles into the tank; substantially as described.

3. In apparatus of the character indicated, a furnace, an article-containing basket adapted to travel through the furnace, a tiltable table to receive the basket from the furnace, a quenching tank, a return conveyor, and means for swinging the tiltable table in two successive movements to provide for dumping the articles into the tank and to carry the empty basket to the conveyor; substantially as described.

4. In apparatus of the character indicated, a quenching tank, a perforated container in the tank to receive heat treated articles, the tank having a portion extended beyond the container, mechanism to elevate the container from the quenching medium, and means for thereafter conveying the container along the top of the extended portion of the tank above the quenching medium to drain the quenching medium into the tank; substantially as described.

5. In apparatus of the character indicated, a quenching tank, a perforated container to receive heat treated articles, a wheeled carrier for the container, elevating mechanism to raise and lower the container and its wheeled carrier into or out of the quenching tank, the elevating mechanism having rails, the quenching tank being extended beyond the wheeled carrier, and rails extending along the extended portion of the tank in line with the rails on the elevating mechanism to provide for draining liquid from the container into said extended portion as the Wheeled carrier moves away from the elevating mechanism; substantially as described.

6. In apparatus of the character indicated, a furnace, a crane swivelled adjacent to the furnace, a table mounted on the crane to tilt with respect thereto, an article container secured to the table, means carried by the crane to control tilting of the table and container to an inverted position, and a quenching tank to receive articles from the container; substantially as described.

7. In apparatus of the character indicated, a furnace, a crane swivelled adjacent to the furnace, a shaft journalled on the crane, a table secured to the shaft and adapted to receive an article containing basket from the furnace, means for securing the basket to the table, and means for rocking the shaft to control tilting of the table and basket to inverted position for dumping of the articles from the basket; substantially as described.

8. In apparatus of the character indicated, a furnace, a table adapted to receive an articlecontaining basket from the furnace, standards projecting upwardly from opposite sides of the table and having retaining lugs overlying the basket, means for holding the basket from shifting out from under the lugs, and means for tilting the table to dump the articles from the basket; substantially as described.

9. In apparatus of the character indicated, a furnace, a quenching tank, an arm swivelled on a substantially vertical axis adjacent to the furnace, a table mounted on the end portion of the arm to travel bodily from the furnace outlet to the tank, an article containing basket adapted to slide out of the furnace onto the table, means for securing the basket to the table, a rock shaft for pivotally connecting the table to the arm, and power operated means carried by the arm and connected to the rock shaft for tilting the table and basket over the quenching tank.

10. In apparatus of the character indicated, a furnace, a quenching tank, an arm swivelled on a substantially vertical axis adjacent to the furnace, a table mounted on the end portion of the arm to travel bodily from the furnaceoutlet to ket rearwardly and laterally from the furnace outlet to a dumping position over the tank, and

the same carrier means having a mounting conof travel over the top of and beyond the quenchstructed and arranged to provide a further field ing tank to carry the empty basket to the conthe tank, an article containing basket adapted to slide out of the furnace onto the table, means for securing the basket to the table, and a pivotal connection between the table and the arm to provide for inverting the table and basket over the quenching tank.

11. In apparatus of the character indicated, a furnace, a quenching tank, an arm swivelled on a substantially vertical axis adjacent to the furnace, a table mounted on the end portion of the arm to travel bodily from the furnace outlet to the tank, a rock shaft for pivotally connectveyor for return thereby to the other end of the furnace.

13. In apparatus of the character indicated, a furnace, a quenching tankfto one side of and beyond one end of the furnace, a return conveyor alongside of the furnace, an arm swivelled on a substantially vertical axis to swing from the furnace outlet to the quenching tank, an,

article containing basket adapted to slide out of the furnace to a supported'position on the arm, means for overturning the basket over the quenching tank to discharge the articles, and the arm having a further field of swing over the tank to the conveyor to carry the empty basket to the conveyor for return thereby to the other end of the furnace.

14. In apparatus-of the character indicated, a furnace, a quenching tank to one side of and beyond one end of the furnace, a return conveyor alongside of the furnace, an arm swivelled on a substantially vertical axis to swing from the furnace outlet to the tank, a table tiltably mounted on the arm, an article containing basket adapted to slide out of the furnace onto the table, means for tilting the table and basket over the tank to discharge the articles into the quenching tank and to right the table and empty basket, and the arm having a further field of swing over and beyond the tank towards the conveyor to carry the empty basket to the conveyor for return thereby to the other end of the furnace.

15. In apparatus of the character indicated, a furnace, a quenching tank to one side of and beyond one end of the furnace, a return conveyor alongside of the furnace, an arm swivelled on a substantially vertical axis to swing from the furnace outlet to the quenching tank, a table on the arm, an article containing basket adapted to slide out of the furnace onto the table, a latch to limit the movement of the basket, means for tilting the table and the basket to discharge the articles into the quenching tank, the arm having a further field of swing over the tank to the conveyor, and means for operating the latch to provide for sliding the basket from the table to the conveyor. 7

JOHN M. NAIRN.

WILLIAM G. JACKSON.

7 CERTIFICATE OF CORRECTIQN. I Patent No. 2,2L 9,219. I July 15, 19m.

JOHN M. NAIRN, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction 'as follows: Page 5, second column, line 11;, claim 12, strike out the words and syllable "of travel over the top of and beyond the quench-" and insert the same after "field" in line 15, same claim; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 2nd day of September, A. D. 1941.

Henry Van Arsdale, (Seal)- Acting Commissioner of Patent 

